What is an Automatic Transfer Switch?
An Automatic Transfer Switch (ATS) is the brain of any standby power system. It continuously monitors utility power and automatically switches the electrical load to the generator when a power failure is detected.
How an ATS Works
- Monitoring: The ATS constantly monitors utility voltage. If power drops below 80% for 3-5 seconds, it signals the generator to start.
- Transfer: Once the generator reaches operating speed, the ATS transfers the load. This typically takes 10-30 seconds.
- Stabilization: The generator supplies power while the ATS continues to monitor utility power.
- Retransfer: When utility power returns and stabilizes, the ATS transfers back and signals the generator to cool down and shut off.
Types of Transfer Switches
- Open Transition (Break-Before-Make): Most common. Brief 50-100ms interruption during transfer. Suitable for most applications.
- Closed Transition (Make-Before-Break): Zero interruption. Required for data centers, hospitals, and financial institutions.
- Delayed Transition: Programmed delay between disconnection and reconnection. Used for large motors.
- Manual Transfer Switch: Requires operator to throw the switch. More affordable for less critical applications.
Sizing Your Transfer Switch
Common sizes: 30A, 70A, 100A, 200A, 400A, 800A, 1200A. Must match generator output rating, system voltage, and number of poles.
Jinjia Power's ATS Solutions
Jinjia Power offers a complete range of automatic transfer switches from 30A to 1200A, featuring industrial-grade mechanisms with 10,000+ cycle life, UL1008 compliant design, and microprocessor-based logic control.
Browse our complete ATS product range or contact our experts.